1. Field of the Invention
The present invention relates to an adaptor for setting a self-drilling, chemically anchorable, fastening element and including a rotor member rotatably supported in the adaptor housing and extending along a longitudinal axis and having a coupling section provided at its first end for connecting the rotor member with a drilling tool for joint rotation therewith, a coupling receptacle provided at a second end of the rotor member opposite the first end for fixedly receiving a free end of the fastening element for joint rotation of the fastening element with the rotor member, and a feeding channel for an ejection medium and opening into the coupling receptacle. A connection channel section for connects a connection opening provided in the housing for the ejection medium with the feeding channel of the rotor member. Support elements are provided between the housing and the rotor member for rotatably supporting the rotor member, and sealing elements are provided also between the housing and rotor member for sealing the connection channel section.
2. Description of the Prior Art
Self-drilling, chemically anchorable, fastening elements used in construction and, in particular, self-drilling, chemically anchorable rock anchors for use in mine and tunnel regions are known for a long time. They are used primarily for stabilization of excavation or of walls in hollow spaces such as tunnels, galleries, and the like. During formation of cavities and hollow spaces, mechanical properties and, in particular, the load-carrying capacity of rock layers diminish. These rock layers are anchored with chemically anchorable fastening elements to further located, undamaged rock layers, securing them to the undamaged layers.
German Publication DE 100 17 763 A1 discloses a self-drilling, chemically anchorable, fastening element having an anchor tube provided with a drilling head at one of its ends and an engagement element for the drilling tool at its other, free end. In the tubular member, there are provided a receptacle for the ejectable mass in which the ejectable mass itself and an ejection piston are located. In the first step, the fastening element, which is driven by the drilling tool, is drilled into a constructional component. In a further step, e.g., after the drilling tool has been disconnected, an ejection device is secured on the engagement element, and the to-be-ejected mass is forced out in the direction of the drilling head by an ejection mechanism. The forced-out mass flows through outlet openings in the drilling head toward the borehole bottom and in an annular gap between the borehole wall and the anchor tube. After the forced-out mass has hardened, the fastening element is anchored in the constructional component.
German Publication DE 103 34 374 A1 discloses an adaptor for setting a self-drilling, chemically anchorable, fastening element in a constructional component, i.e., for drilling the fastening element into the constructional component and for a subsequent forcing-out of the hardenable mass stored in the fastening element. The adaptor has a housing and rotor member rotatably supported in the housing and extending along a longitudinal axis. The rotor member has a coupling section provided at its first end for connecting the rotor member with a drilling tool for joint rotation therewith, and a coupling receptacle provided at a second end of the rotor member opposite the first end for fixedly receiving a free end of the fastening element for joint rotation of the fastening element with the rotor member. In the rotor member, there is provided a feeding channel for an ejection medium and which opens into the coupling receptacle. In the housing, there is provided a connection opening for an ejection medium. A connection channel section connects the connection opening with the feeding channel of the rotor member.
Between the housing and the rotor member, there are provided support elements for rotatably supporting the rotor member and which are spaced from the outer rim of the housing. Between the housing and the rotor member, there are also provided sealing elements for sealing the connection channel section. The sealing elements are spaced from the support elements.
Water under high pressure is used as an ejection medium for forcing out the hardenable mass from the fastening element. In addition, there is provided a second, rinsing water channel extending in the axial direction of the rotor member. During the drilling process, rinsing water is fed to the drilling head of the fastening element through this channel. Also, drillings from the region of the drilling head can be removed through channel.
The adaptor of DE 103 34 374 A1 provides for drilling and subsequent forcing out of a hardenable material, without a need to disconnect the drilling tool and to provide a separate ejection device for ejecting the hardenable mass contained in the fastening element. This substantially reduces the costs associated with setting of a fastening element.
However, the drawback of the known device consists in that upon wear of sealing elements, the resulting leakage leads to the damage of support elements and makes manufacturing and maintenance of the adaptor more expensive.
Accordingly, an object of the present invention is to provide an adaptor of the type described above having a simplified design and service-friendly.